Protector for drill pipes



Jan. 12, 1943. J. c. BALLAGH 2,308,147

PROTECTOR FOR DRILL PIPES Filed Oct. 12, 1940 Patented Jan. 12, 1943UNITED STATES PATENT [OFFICE PROTECTOR FOR DRILL PIPES James O. Ballagh,Los Angeles, Calii'., assignor. to

Patters on-Ballagh Corporation, Los Angeles,

Calii'.,-a corporation oi California Application October-12, 1940,Serial No. 360,913

3 Claims. (01. 308-4) The present invention relates to an improvement inrubber protectors employed upon drilling pipe.

For the protection of drill pipe, such as employed in a rotary system ofdrilling oil wells,

are to be applied, and they are applied to the drill pipe by beingstretched over the same. As the protector sleeves have been constructedin the past, it is found that the drill pipe undergoes considerable wearadjacent the ends of the protectors. This is believed to be due to thefact that the drilling fluid circulated during drilling operationsundergoes a swirling action at the ends of the protector sleeves,particularly at the top of the sleeve, with the result that the drillingmud cuts a ring in the drill pipe above the proteetor.

It is a general object of the present invention to provide a protectorfor drill pipe which will eliminate the destruction of the drill pipewhich is attendant through the use of the present forms of protector.

I have found that by providing protector sleeves with extending rings attheir ends, which rings have a larger interior diameter than thediameter of the bore 01- the main body of the sleeve.

the cutting of the drill pipe by the mud fluid characterized by the useof the present form or protector sleeves can be substantially entirelyeliminated. I have further found that such rings facilitate theinstallation of the protector ,sleeve on the pipe in that such rings maybe employed for holding extra lubricant to be used in installing therings.

The improved protector sleeve of the present invention will best beunderstood from a description of a preferred form or example ofprotector sleeve embodying the present invention. I have, therefore,described the preierrediorm or forms of protector sleeve of the presentinvention in connection with the accompanying drawing, in which- Figure1 is an elevation in vertical section 01' one form oi the protectorsleeve.

Figure 2 is an elevation in vertical section of the protector sleeve asapplied to a drill pipe.

Figure 3 is an elevation in section of a modified form of protectorsleeve.

P pe. 7

Referring, first, to Figures 1 and 2.01 the drawing, the protector ofthe present invention consists of a body 2 which is formed of rubberinaccordance with the usual or preferred practice. The body 2 provides acentral bore 3, which is normally of a diameter considerably smallerthan the diameter of the drill pipe 4 to which the protector is to beapplied. The body 2 or the protector is a cylindrical body, preferablychamfered I at its ends, as indicated at 5 and 6. From the ends of thebody protector I extend the annular lips I. The lips I are provided withan interior diameter somewhat larger than the center bore 3 of .theprotector to provide the shoulders 8,

which may be employed for lubricant during the act oi installing theprotector upon the pipe 4. With the protectors of the form indicated inFigure 1 it is found that when such protectors are stretched over adrill pipe theends of the lips I are curved against the drill pipe inthe manner indicated in Figure 2, thereby covering that portion of thedrill pipe which in usual practice is cut by the action of the drillingfluid in the well. The lips I of the protector apparently breakup theeddy currents at the ends of the protector, thereby preserving the drillpipe ,4 from deterioration.

Now, referring to Figures 3 and 4, I have shown a somewhat modified formofprotector in which 8 indicates the cylindrical tector and III thebore. The protector is preferably beveled or chamfered at its ends,as.indicated at H and It. To form the projecting lips indicated at l3 atthe end of the proJector,I undercut the ends of the protector asindicated at It. With this form of protector the projecting lips l3iormed by theundercut l4 function similar in manner to the lips I(previously described. When the protector is stretched over a drillpipe, such as indicated'at ii in Figure 4, the projecting lips l3 arecurved into contact with the pipe, providing smooth surfaces at the endsof the protector which function to eliminate any eddy currents.

While the particular forms 01 Protector herein described are welladapted to carry out the objects oi the invention, variousmodificationsand changes may be made, and this invention isoi I slightlyFigure 4 is an elevation in section of the protector sleeve of Figure 3as applied to a drill body of the pro- I claim:

1. In a rubber protector for drill pipes, 9. cylindrical body memberhaving a central bore of normally smaller inner diameter than the outerdiameter of the drill pipe to which the protector is to be applied, andan angular hp at the end of the protector having an inner diameterlarger than the inner diameter of the body of the protector, said memberbeing adapted to be stretched over the drill pipe and to provide anelastic force for g pping the member to the drill pipe, said lip adaptedto be curved inwardly into contact with the drill pipe through theaction 01'- stretching the protector over the drill pipe.

2. A rubber protector for drill pipes,'which protector comprises acylindrical body having a central bore of smaller inner diameterthan theouter diameter of the pipe to which the protector is to be applied andadapted to be stretched over the pipe and resiliently grip the pipe, anintegral portion 01 the protector at at least one end thereof forming alip having a larger irmer diameter than the innerdiameter otthe body ofthe protector, said lip being adapted to curve towards the drill pipe asthe protector is stretched over the pipe.

3. A rubber protector for drill pipes, consisting of a body part havinga central bore of smaller inner diameter than the outer diameter or thepipe to which the same is to be applied, and an undercut at one end ofsaid body forming a lip having a larger interior diameter than the innerdiameter of the body 01 the protector and being adapted to curve towardsa drill pipe when the body or the protector is stretched over the same,

the body part being adapted to resiliently grip said drill pipe andstretch thereover.

. JAMES C. BALLAGH.

